:root {
    /* Color Palette - Modern, vibrant gradients */
    --primary-gradient: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    --secondary-gradient: linear-gradient(135deg, #f093fb 0%, #f5576c 100%);
    --success-gradient: linear-gradient(135deg, #4facfe 0%, #00f2fe 100%);
    --background-dark: #0f0f1e;
    --background-card: rgba(255, 255, 255, 0.05);
    --background-card-hover: rgba(255, 255, 255, 0.08);
    --text-primary: #ffffff;
    --text-secondary: #a0a0b8;
    --text-muted: #6b6b8a;
    --border-color: rgba(255, 255, 255, 0.1);
    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.1);
    --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.2);
    --shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.3);
    --shadow-glow: 0 0 20px rgba(102, 126, 234, 0.3);

    /* Spacing */
    --spacing-xs: 0.5rem;
    --spacing-sm: 0.75rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --spacing-2xl: 3rem;

    /* Border Radius */
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --radius-xl: 20px;

    /* Transitions */
    --transition-fast: 150ms ease-in-out;
    --transition-normal: 300ms ease-in-out;
    --transition-slow: 500ms ease-in-out;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    background: var(--background-dark);
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
    overflow-x: hidden;
}

/* Animated background gradient */
body::before {
    content: '';
    position: fixed;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle, rgba(102, 126, 234, 0.1) 0%, transparent 50%);
    animation: rotateGradient 20s linear infinite;
    pointer-events: none;
    z-index: 0;
}

@keyframes rotateGradient {
    0% {
        transform: rotate(0deg);
    }

    100% {
        transform: rotate(360deg);
    }
}

.container {
    max-width: 900px;
    margin: 0 auto;
    padding: var(--spacing-xl) var(--spacing-lg);
    position: relative;
    z-index: 1;
}

/* Header */
.header {
    text-align: center;
    margin-bottom: var(--spacing-2xl);
    animation: fadeInDown 0.6s ease-out;
}

.title {
    font-size: 3rem;
    font-weight: 700;
    background: var(--primary-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: var(--spacing-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-md);
}

.title-icon {
    font-size: 2.5rem;
    animation: float 3s ease-in-out infinite;
}

@keyframes float {

    0%,
    100% {
        transform: translateY(0px);
    }

    50% {
        transform: translateY(-10px);
    }
}

.subtitle {
    color: var(--text-secondary);
    font-size: 1.125rem;
    font-weight: 400;
}

/* Cards */
.card {
    background: var(--background-card);
    backdrop-filter: blur(10px);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: var(--spacing-xl);
    margin-bottom: var(--spacing-lg);
    transition: all var(--transition-normal);
    animation: fadeInUp 0.6s ease-out;
}

.card:hover {
    background: var(--background-card-hover);
    box-shadow: var(--shadow-md);
    transform: translateY(-2px);
}

.card-label {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    font-size: 0.875rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--text-secondary);
    margin-bottom: var(--spacing-md);
}

.label-icon {
    font-size: 1.25rem;
}

/* Model Selector */
.model-select {
    width: 100%;
    padding: var(--spacing-md) var(--spacing-lg);
    font-size: 1rem;
    font-family: 'Inter', sans-serif;
    background: rgba(255, 255, 255, 0.08);
    color: var(--text-primary);
    border: 2px solid var(--border-color);
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all var(--transition-fast);
    outline: none;
}

.model-select:hover {
    border-color: rgba(102, 126, 234, 0.5);
    background: rgba(255, 255, 255, 0.1);
}

.model-select:focus {
    border-color: #667eea;
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.2);
}

.model-select option {
    background: #1a1a2e;
    color: var(--text-primary);
    padding: var(--spacing-sm);
}

.model-info {
    margin-top: var(--spacing-md);
    padding: var(--spacing-md);
    background: rgba(102, 126, 234, 0.1);
    border-left: 3px solid #667eea;
    border-radius: var(--radius-sm);
    font-size: 0.875rem;
    color: var(--text-secondary);
}

/* Text Input */
.textarea-wrapper {
    position: relative;
}

.text-display {
    width: 100%;
    min-height: 150px;
    padding: var(--spacing-lg);
    font-size: 1.125rem;
    font-family: 'Inter', sans-serif;
    background: rgba(255, 255, 255, 0.03);
    color: var(--text-primary);
    border: 2px solid var(--border-color);
    border-radius: var(--radius-md);
    outline: none;
    transition: all var(--transition-fast);
    line-height: 1.8;
    word-wrap: break-word;
    overflow-wrap: break-word;
}

.text-display:empty::before {
    content: attr(data-placeholder);
    color: var(--text-muted);
    font-style: italic;
}

.text-display:focus {
    border-color: #667eea;
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.2);
    background: rgba(255, 255, 255, 0.05);
}

.text-display .word {
    cursor: pointer;
    padding: 2px 4px;
    border-radius: 4px;
    transition: all var(--transition-fast);
}

.text-display .word:hover {
    background: rgba(102, 126, 234, 0.2);
    color: #a0cfff;
}

.text-display .word.selected {
    background: var(--primary-gradient);
    color: white;
    font-weight: 600;
}

.input-hint {
    margin-top: var(--spacing-md);
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    color: var(--text-muted);
    font-size: 0.875rem;
}

.hint-icon {
    font-size: 1rem;
}

/* Use Default Button */
.use-default-btn {
    margin-top: var(--spacing-md);
    padding: var(--spacing-sm) var(--spacing-lg);
    background: var(--primary-gradient);
    color: white;
    border: none;
    border-radius: var(--radius-md);
    font-size: 0.875rem;
    font-weight: 600;
    font-family: 'Inter', sans-serif;
    cursor: pointer;
    transition: all var(--transition-fast);
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-sm);
    box-shadow: var(--shadow-sm);
}

.use-default-btn:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-md), var(--shadow-glow);
}

.use-default-btn:active {
    transform: translateY(0);
}

.use-default-btn .btn-icon {
    font-size: 1rem;
}


/* Suggestions */
.suggestions-card {
    display: none;
}

.suggestions-card.active {
    display: block;
    animation: fadeInUp 0.4s ease-out;
}

.suggestions-header {
    margin-bottom: var(--spacing-lg);
}

.suggestions-container {
    display: grid;
    gap: var(--spacing-md);
}

.empty-state {
    text-align: center;
    padding: var(--spacing-xl);
    color: var(--text-muted);
}

.empty-state-icon {
    font-size: 3rem;
    margin-bottom: var(--spacing-md);
    animation: bounce 2s ease-in-out infinite;
}

@keyframes bounce {

    0%,
    100% {
        transform: translateY(0);
    }

    50% {
        transform: translateY(-10px);
    }
}

.suggestion-item {
    background: rgba(255, 255, 255, 0.05);
    border: 2px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: var(--spacing-lg);
    cursor: pointer;
    transition: all var(--transition-fast);
    position: relative;
    overflow: hidden;
}

.suggestion-item::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: var(--primary-gradient);
    opacity: 0;
    transition: opacity var(--transition-fast);
    z-index: 0;
}

.suggestion-item:hover {
    border-color: #667eea;
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.suggestion-item:hover::before {
    opacity: 0.1;
}

.suggestion-item:active {
    transform: translateY(0);
}

.suggestion-content {
    position: relative;
    z-index: 1;
}

.suggestion-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--spacing-sm);
}

.suggestion-rephrase {
    font-size: 1.125rem;
    font-weight: 600;
    color: var(--text-primary);
}

.suggestion-arrow {
    color: var(--text-muted);
    font-size: 1.25rem;
}

.suggestion-preview {
    color: var(--text-secondary);
    font-size: 0.875rem;
    margin-bottom: var(--spacing-xs);
}

.suggestion-preview .original {
    text-decoration: line-through;
    opacity: 0.6;
}

.suggestion-preview .replacement {
    color: #4facfe;
    font-weight: 500;
}

/* Footer */
.footer {
    text-align: center;
    padding: var(--spacing-xl) 0;
    color: var(--text-muted);
    font-size: 0.875rem;
}

/* Loading Overlay */
.loading-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(15, 15, 30, 0.95);
    backdrop-filter: blur(5px);
    display: none;
    align-items: center;
    justify-content: center;
    flex-direction: column;
    z-index: 1000;
}

.loading-overlay.active {
    display: flex;
}

.loading-spinner {
    width: 60px;
    height: 60px;
    border: 4px solid var(--border-color);
    border-top: 4px solid #667eea;
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    0% {
        transform: rotate(0deg);
    }

    100% {
        transform: rotate(360deg);
    }
}

.loading-text {
    margin-top: var(--spacing-lg);
    font-size: 1.125rem;
    color: var(--text-secondary);
}

/* Animations */
@keyframes fadeInDown {
    from {
        opacity: 0;
        transform: translateY(-20px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* Responsive Design */
@media (max-width: 768px) {
    .container {
        padding: var(--spacing-lg) var(--spacing-md);
    }

    .title {
        font-size: 2rem;
    }

    .subtitle {
        font-size: 1rem;
    }

    .card {
        padding: var(--spacing-lg);
    }
}